[gnome-desktop-testing] Cleaning up Mago code

[Ara Pulido <ara ubuntu com>]

Hello all,

As part of UDS Maverick, we talked about making the Mago code a lot cleaner.

The most important bit of this was splitting the gnome.py and ubuntu.py
into the different applications. Jeff took care of that one.

The next step would be to avoid the unnecessary try/catch blocks that
are all over the application wrappers. The main reason of these blocks
were to give a correct error message, when LDTP didn't give us one.

We are going to avoid these blocks, and, whenever LDTP gives a wrong (or
not clear) error message, we are going to file a bug against LDTP
instead. This will make Mago code cleaner, and we will be improving LDTP.

I have created a branch with this code and I will merge it with trunk,
at least I receive any comments or concerns.

Feel free to share your thoughts here, or in the merge proposal [1]

Thanks!
Ara.

[1] https://code.launchpad.net/~apulido/mago/cleaner_happier/+merge/38923